1 //===--- FormatToken.h - Format C++ code ------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file contains the declaration of the FormatToken, a wrapper
11 /// around Token with additional information related to formatting.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LIB_FORMAT_FORMATTOKEN_H
16 #define LLVM_CLANG_LIB_FORMAT_FORMATTOKEN_H
17 
18 #include "clang/Basic/IdentifierTable.h"
19 #include "clang/Basic/OperatorPrecedence.h"
20 #include "clang/Format/Format.h"
21 #include "clang/Lex/Lexer.h"
22 #include <memory>
23 #include <unordered_set>
24 
25 namespace clang {
26 namespace format {
27 
28 #define LIST_TOKEN_TYPES                                                       \
29   TYPE(ArrayInitializerLSquare)                                                \
30   TYPE(ArraySubscriptLSquare)                                                  \
31   TYPE(AttributeColon)                                                         \
32   TYPE(AttributeParen)                                                         \
33   TYPE(AttributeSquare)                                                        \
34   TYPE(BinaryOperator)                                                         \
35   TYPE(BitFieldColon)                                                          \
36   TYPE(BlockComment)                                                           \
37   TYPE(CastRParen)                                                             \
38   TYPE(ConditionalExpr)                                                        \
39   TYPE(ConflictAlternative)                                                    \
40   TYPE(ConflictEnd)                                                            \
41   TYPE(ConflictStart)                                                          \
42   TYPE(CtorInitializerColon)                                                   \
43   TYPE(CtorInitializerComma)                                                   \
44   TYPE(DesignatedInitializerLSquare)                                           \
45   TYPE(DesignatedInitializerPeriod)                                            \
46   TYPE(DictLiteral)                                                            \
47   TYPE(ForEachMacro)                                                           \
48   TYPE(FunctionAnnotationRParen)                                               \
49   TYPE(FunctionDeclarationName)                                                \
50   TYPE(FunctionLBrace)                                                         \
51   TYPE(FunctionTypeLParen)                                                     \
52   TYPE(ImplicitStringLiteral)                                                  \
53   TYPE(InheritanceColon)                                                       \
54   TYPE(InheritanceComma)                                                       \
55   TYPE(InlineASMBrace)                                                         \
56   TYPE(InlineASMColon)                                                         \
57   TYPE(JavaAnnotation)                                                         \
58   TYPE(JsComputedPropertyName)                                                 \
59   TYPE(JsExponentiation)                                                       \
60   TYPE(JsExponentiationEqual)                                                  \
61   TYPE(JsFatArrow)                                                             \
62   TYPE(JsNonNullAssertion)                                                     \
63   TYPE(JsNullishCoalescingOperator)                                            \
64   TYPE(JsNullPropagatingOperator)                                              \
65   TYPE(JsPrivateIdentifier)                                                    \
66   TYPE(JsTypeColon)                                                            \
67   TYPE(JsTypeOperator)                                                         \
68   TYPE(JsTypeOptionalQuestion)                                                 \
69   TYPE(LambdaArrow)                                                            \
70   TYPE(LambdaLBrace)                                                           \
71   TYPE(LambdaLSquare)                                                          \
72   TYPE(LeadingJavaAnnotation)                                                  \
73   TYPE(LineComment)                                                            \
74   TYPE(MacroBlockBegin)                                                        \
75   TYPE(MacroBlockEnd)                                                          \
76   TYPE(NamespaceMacro)                                                         \
77   TYPE(ObjCBlockLBrace)                                                        \
78   TYPE(ObjCBlockLParen)                                                        \
79   TYPE(ObjCDecl)                                                               \
80   TYPE(ObjCForIn)                                                              \
81   TYPE(ObjCMethodExpr)                                                         \
82   TYPE(ObjCMethodSpecifier)                                                    \
83   TYPE(ObjCProperty)                                                           \
84   TYPE(ObjCStringLiteral)                                                      \
85   TYPE(OverloadedOperator)                                                     \
86   TYPE(OverloadedOperatorLParen)                                               \
87   TYPE(PointerOrReference)                                                     \
88   TYPE(PureVirtualSpecifier)                                                   \
89   TYPE(RangeBasedForLoopColon)                                                 \
90   TYPE(RegexLiteral)                                                           \
91   TYPE(SelectorName)                                                           \
92   TYPE(StartOfName)                                                            \
93   TYPE(StatementMacro)                                                         \
94   TYPE(StructuredBindingLSquare)                                               \
95   TYPE(TemplateCloser)                                                         \
96   TYPE(TemplateOpener)                                                         \
97   TYPE(TemplateString)                                                         \
98   TYPE(ProtoExtensionLSquare)                                                  \
99   TYPE(TrailingAnnotation)                                                     \
100   TYPE(TrailingReturnArrow)                                                    \
101   TYPE(TrailingUnaryOperator)                                                  \
102   TYPE(TypenameMacro)                                                          \
103   TYPE(UnaryOperator)                                                          \
104   TYPE(CSharpStringLiteral)                                                    \
105   TYPE(CSharpNullCoalescing)                                                   \
106   TYPE(Unknown)
107 
108 enum TokenType {
109 #define TYPE(X) TT_##X,
110   LIST_TOKEN_TYPES
111 #undef TYPE
112       NUM_TOKEN_TYPES
113 };
114 
115 /// Determines the name of a token type.
116 const char *getTokenTypeName(TokenType Type);
117 
118 // Represents what type of block a set of braces open.
119 enum BraceBlockKind { BK_Unknown, BK_Block, BK_BracedInit };
120 
121 // The packing kind of a function's parameters.
122 enum ParameterPackingKind { PPK_BinPacked, PPK_OnePerLine, PPK_Inconclusive };
123 
124 enum FormatDecision { FD_Unformatted, FD_Continue, FD_Break };
125 
126 class TokenRole;
127 class AnnotatedLine;
128 
129 /// A wrapper around a \c Token storing information about the
130 /// whitespace characters preceding it.
131 struct FormatToken {
132   FormatToken() {}
133 
134   /// The \c Token.
135   Token Tok;
136 
137   /// The number of newlines immediately before the \c Token.
138   ///
139   /// This can be used to determine what the user wrote in the original code
140   /// and thereby e.g. leave an empty line between two function definitions.
141   unsigned NewlinesBefore = 0;
142 
143   /// Whether there is at least one unescaped newline before the \c
144   /// Token.
145   bool HasUnescapedNewline = false;
146 
147   /// The range of the whitespace immediately preceding the \c Token.
148   SourceRange WhitespaceRange;
149 
150   /// The offset just past the last '\n' in this token's leading
151   /// whitespace (relative to \c WhiteSpaceStart). 0 if there is no '\n'.
152   unsigned LastNewlineOffset = 0;
153 
154   /// The width of the non-whitespace parts of the token (or its first
155   /// line for multi-line tokens) in columns.
156   /// We need this to correctly measure number of columns a token spans.
157   unsigned ColumnWidth = 0;
158 
159   /// Contains the width in columns of the last line of a multi-line
160   /// token.
161   unsigned LastLineColumnWidth = 0;
162 
163   /// Whether the token text contains newlines (escaped or not).
164   bool IsMultiline = false;
165 
166   /// Indicates that this is the first token of the file.
167   bool IsFirst = false;
168 
169   /// Whether there must be a line break before this token.
170   ///
171   /// This happens for example when a preprocessor directive ended directly
172   /// before the token.
173   bool MustBreakBefore = false;
174 
175   /// The raw text of the token.
176   ///
177   /// Contains the raw token text without leading whitespace and without leading
178   /// escaped newlines.
179   StringRef TokenText;
180 
181   /// Set to \c true if this token is an unterminated literal.
182   bool IsUnterminatedLiteral = 0;
183 
184   /// Contains the kind of block if this token is a brace.
185   BraceBlockKind BlockKind = BK_Unknown;
186 
187   TokenType Type = TT_Unknown;
188 
189   /// The number of spaces that should be inserted before this token.
190   unsigned SpacesRequiredBefore = 0;
191 
192   /// \c true if it is allowed to break before this token.
193   bool CanBreakBefore = false;
194 
195   /// \c true if this is the ">" of "template<..>".
196   bool ClosesTemplateDeclaration = false;
197 
198   /// Number of parameters, if this is "(", "[" or "<".
199   unsigned ParameterCount = 0;
200 
201   /// Number of parameters that are nested blocks,
202   /// if this is "(", "[" or "<".
203   unsigned BlockParameterCount = 0;
204 
205   /// If this is a bracket ("<", "(", "[" or "{"), contains the kind of
206   /// the surrounding bracket.
207   tok::TokenKind ParentBracket = tok::unknown;
208 
209   /// A token can have a special role that can carry extra information
210   /// about the token's formatting.
211   std::unique_ptr<TokenRole> Role;
212 
213   /// If this is an opening parenthesis, how are the parameters packed?
214   ParameterPackingKind PackingKind = PPK_Inconclusive;
215 
216   /// The total length of the unwrapped line up to and including this
217   /// token.
218   unsigned TotalLength = 0;
219 
220   /// The original 0-based column of this token, including expanded tabs.
221   /// The configured TabWidth is used as tab width.
222   unsigned OriginalColumn = 0;
223 
224   /// The length of following tokens until the next natural split point,
225   /// or the next token that can be broken.
226   unsigned UnbreakableTailLength = 0;
227 
228   // FIXME: Come up with a 'cleaner' concept.
229   /// The binding strength of a token. This is a combined value of
230   /// operator precedence, parenthesis nesting, etc.
231   unsigned BindingStrength = 0;
232 
233   /// The nesting level of this token, i.e. the number of surrounding (),
234   /// [], {} or <>.
235   unsigned NestingLevel = 0;
236 
237   /// The indent level of this token. Copied from the surrounding line.
238   unsigned IndentLevel = 0;
239 
240   /// Penalty for inserting a line break before this token.
241   unsigned SplitPenalty = 0;
242 
243   /// If this is the first ObjC selector name in an ObjC method
244   /// definition or call, this contains the length of the longest name.
245   ///
246   /// This being set to 0 means that the selectors should not be colon-aligned,
247   /// e.g. because several of them are block-type.
248   unsigned LongestObjCSelectorName = 0;
249 
250   /// If this is the first ObjC selector name in an ObjC method
251   /// definition or call, this contains the number of parts that the whole
252   /// selector consist of.
253   unsigned ObjCSelectorNameParts = 0;
254 
255   /// The 0-based index of the parameter/argument. For ObjC it is set
256   /// for the selector name token.
257   /// For now calculated only for ObjC.
258   unsigned ParameterIndex = 0;
259 
260   /// Stores the number of required fake parentheses and the
261   /// corresponding operator precedence.
262   ///
263   /// If multiple fake parentheses start at a token, this vector stores them in
264   /// reverse order, i.e. inner fake parenthesis first.
265   SmallVector<prec::Level, 4> FakeLParens;
266   /// Insert this many fake ) after this token for correct indentation.
267   unsigned FakeRParens = 0;
268 
269   /// \c true if this token starts a binary expression, i.e. has at least
270   /// one fake l_paren with a precedence greater than prec::Unknown.
271   bool StartsBinaryExpression = false;
272   /// \c true if this token ends a binary expression.
273   bool EndsBinaryExpression = false;
274 
275   /// If this is an operator (or "."/"->") in a sequence of operators
276   /// with the same precedence, contains the 0-based operator index.
277   unsigned OperatorIndex = 0;
278 
279   /// If this is an operator (or "."/"->") in a sequence of operators
280   /// with the same precedence, points to the next operator.
281   FormatToken *NextOperator = nullptr;
282 
283   /// Is this token part of a \c DeclStmt defining multiple variables?
284   ///
285   /// Only set if \c Type == \c TT_StartOfName.
286   bool PartOfMultiVariableDeclStmt = false;
287 
288   /// Does this line comment continue a line comment section?
289   ///
290   /// Only set to true if \c Type == \c TT_LineComment.
291   bool ContinuesLineCommentSection = false;
292 
293   /// If this is a bracket, this points to the matching one.
294   FormatToken *MatchingParen = nullptr;
295 
296   /// The previous token in the unwrapped line.
297   FormatToken *Previous = nullptr;
298 
299   /// The next token in the unwrapped line.
300   FormatToken *Next = nullptr;
301 
302   /// If this token starts a block, this contains all the unwrapped lines
303   /// in it.
304   SmallVector<AnnotatedLine *, 1> Children;
305 
306   /// Stores the formatting decision for the token once it was made.
307   FormatDecision Decision = FD_Unformatted;
308 
309   /// If \c true, this token has been fully formatted (indented and
310   /// potentially re-formatted inside), and we do not allow further formatting
311   /// changes.
312   bool Finalized = false;
313 
314   bool is(tok::TokenKind Kind) const { return Tok.is(Kind); }
315   bool is(TokenType TT) const { return Type == TT; }
316   bool is(const IdentifierInfo *II) const {
317     return II && II == Tok.getIdentifierInfo();
318   }
319   bool is(tok::PPKeywordKind Kind) const {
320     return Tok.getIdentifierInfo() &&
321            Tok.getIdentifierInfo()->getPPKeywordID() == Kind;
322   }
323   template <typename A, typename B> bool isOneOf(A K1, B K2) const {
324     return is(K1) || is(K2);
325   }
326   template <typename A, typename B, typename... Ts>
327   bool isOneOf(A K1, B K2, Ts... Ks) const {
328     return is(K1) || isOneOf(K2, Ks...);
329   }
330   template <typename T> bool isNot(T Kind) const { return !is(Kind); }
331 
332   bool isIf(bool AllowConstexprMacro = true) const {
333     return is(tok::kw_if) || endsSequence(tok::kw_constexpr, tok::kw_if) ||
334            (endsSequence(tok::identifier, tok::kw_if) && AllowConstexprMacro);
335   }
336 
337   bool closesScopeAfterBlock() const {
338     if (BlockKind == BK_Block)
339       return true;
340     if (closesScope())
341       return Previous->closesScopeAfterBlock();
342     return false;
343   }
344 
345   /// \c true if this token starts a sequence with the given tokens in order,
346   /// following the ``Next`` pointers, ignoring comments.
347   template <typename A, typename... Ts>
348   bool startsSequence(A K1, Ts... Tokens) const {
349     return startsSequenceInternal(K1, Tokens...);
350   }
351 
352   /// \c true if this token ends a sequence with the given tokens in order,
353   /// following the ``Previous`` pointers, ignoring comments.
354   /// For example, given tokens [T1, T2, T3], the function returns true if
355   /// 3 tokens ending at this (ignoring comments) are [T3, T2, T1]. In other
356   /// words, the tokens passed to this function need to the reverse of the
357   /// order the tokens appear in code.
358   template <typename A, typename... Ts>
359   bool endsSequence(A K1, Ts... Tokens) const {
360     return endsSequenceInternal(K1, Tokens...);
361   }
362 
363   bool isStringLiteral() const { return tok::isStringLiteral(Tok.getKind()); }
364 
365   bool isObjCAtKeyword(tok::ObjCKeywordKind Kind) const {
366     return Tok.isObjCAtKeyword(Kind);
367   }
368 
369   bool isAccessSpecifier(bool ColonRequired = true) const {
370     return isOneOf(tok::kw_public, tok::kw_protected, tok::kw_private) &&
371            (!ColonRequired || (Next && Next->is(tok::colon)));
372   }
373 
374   /// Determine whether the token is a simple-type-specifier.
375   bool isSimpleTypeSpecifier() const;
376 
377   bool isObjCAccessSpecifier() const {
378     return is(tok::at) && Next &&
379            (Next->isObjCAtKeyword(tok::objc_public) ||
380             Next->isObjCAtKeyword(tok::objc_protected) ||
381             Next->isObjCAtKeyword(tok::objc_package) ||
382             Next->isObjCAtKeyword(tok::objc_private));
383   }
384 
385   /// Returns whether \p Tok is ([{ or an opening < of a template or in
386   /// protos.
387   bool opensScope() const {
388     if (is(TT_TemplateString) && TokenText.endswith("${"))
389       return true;
390     if (is(TT_DictLiteral) && is(tok::less))
391       return true;
392     return isOneOf(tok::l_paren, tok::l_brace, tok::l_square,
393                    TT_TemplateOpener);
394   }
395   /// Returns whether \p Tok is )]} or a closing > of a template or in
396   /// protos.
397   bool closesScope() const {
398     if (is(TT_TemplateString) && TokenText.startswith("}"))
399       return true;
400     if (is(TT_DictLiteral) && is(tok::greater))
401       return true;
402     return isOneOf(tok::r_paren, tok::r_brace, tok::r_square,
403                    TT_TemplateCloser);
404   }
405 
406   /// Returns \c true if this is a "." or "->" accessing a member.
407   bool isMemberAccess() const {
408     return isOneOf(tok::arrow, tok::period, tok::arrowstar) &&
409            !isOneOf(TT_DesignatedInitializerPeriod, TT_TrailingReturnArrow,
410                     TT_LambdaArrow, TT_LeadingJavaAnnotation);
411   }
412 
413   bool isUnaryOperator() const {
414     switch (Tok.getKind()) {
415     case tok::plus:
416     case tok::plusplus:
417     case tok::minus:
418     case tok::minusminus:
419     case tok::exclaim:
420     case tok::tilde:
421     case tok::kw_sizeof:
422     case tok::kw_alignof:
423       return true;
424     default:
425       return false;
426     }
427   }
428 
429   bool isBinaryOperator() const {
430     // Comma is a binary operator, but does not behave as such wrt. formatting.
431     return getPrecedence() > prec::Comma;
432   }
433 
434   bool isTrailingComment() const {
435     return is(tok::comment) &&
436            (is(TT_LineComment) || !Next || Next->NewlinesBefore > 0);
437   }
438 
439   /// Returns \c true if this is a keyword that can be used
440   /// like a function call (e.g. sizeof, typeid, ...).
441   bool isFunctionLikeKeyword() const {
442     switch (Tok.getKind()) {
443     case tok::kw_throw:
444     case tok::kw_typeid:
445     case tok::kw_return:
446     case tok::kw_sizeof:
447     case tok::kw_alignof:
448     case tok::kw_alignas:
449     case tok::kw_decltype:
450     case tok::kw_noexcept:
451     case tok::kw_static_assert:
452     case tok::kw___attribute:
453       return true;
454     default:
455       return false;
456     }
457   }
458 
459   /// Returns \c true if this is a string literal that's like a label,
460   /// e.g. ends with "=" or ":".
461   bool isLabelString() const {
462     if (!is(tok::string_literal))
463       return false;
464     StringRef Content = TokenText;
465     if (Content.startswith("\"") || Content.startswith("'"))
466       Content = Content.drop_front(1);
467     if (Content.endswith("\"") || Content.endswith("'"))
468       Content = Content.drop_back(1);
469     Content = Content.trim();
470     return Content.size() > 1 &&
471            (Content.back() == ':' || Content.back() == '=');
472   }
473 
474   /// Returns actual token start location without leading escaped
475   /// newlines and whitespace.
476   ///
477   /// This can be different to Tok.getLocation(), which includes leading escaped
478   /// newlines.
479   SourceLocation getStartOfNonWhitespace() const {
480     return WhitespaceRange.getEnd();
481   }
482 
483   prec::Level getPrecedence() const {
484     return getBinOpPrecedence(Tok.getKind(), /*GreaterThanIsOperator=*/true,
485                               /*CPlusPlus11=*/true);
486   }
487 
488   /// Returns the previous token ignoring comments.
489   FormatToken *getPreviousNonComment() const {
490     FormatToken *Tok = Previous;
491     while (Tok && Tok->is(tok::comment))
492       Tok = Tok->Previous;
493     return Tok;
494   }
495 
496   /// Returns the next token ignoring comments.
497   const FormatToken *getNextNonComment() const {
498     const FormatToken *Tok = Next;
499     while (Tok && Tok->is(tok::comment))
500       Tok = Tok->Next;
501     return Tok;
502   }
503 
504   /// Returns \c true if this tokens starts a block-type list, i.e. a
505   /// list that should be indented with a block indent.
506   bool opensBlockOrBlockTypeList(const FormatStyle &Style) const {
507     if (is(TT_TemplateString) && opensScope())
508       return true;
509     return is(TT_ArrayInitializerLSquare) || is(TT_ProtoExtensionLSquare) ||
510            (is(tok::l_brace) &&
511             (BlockKind == BK_Block || is(TT_DictLiteral) ||
512              (!Style.Cpp11BracedListStyle && NestingLevel == 0))) ||
513            (is(tok::less) && (Style.Language == FormatStyle::LK_Proto ||
514                               Style.Language == FormatStyle::LK_TextProto));
515   }
516 
517   /// Returns whether the token is the left square bracket of a C++
518   /// structured binding declaration.
519   bool isCppStructuredBinding(const FormatStyle &Style) const {
520     if (!Style.isCpp() || isNot(tok::l_square))
521       return false;
522     const FormatToken *T = this;
523     do {
524       T = T->getPreviousNonComment();
525     } while (T && T->isOneOf(tok::kw_const, tok::kw_volatile, tok::amp,
526                              tok::ampamp));
527     return T && T->is(tok::kw_auto);
528   }
529 
530   /// Same as opensBlockOrBlockTypeList, but for the closing token.
531   bool closesBlockOrBlockTypeList(const FormatStyle &Style) const {
532     if (is(TT_TemplateString) && closesScope())
533       return true;
534     return MatchingParen && MatchingParen->opensBlockOrBlockTypeList(Style);
535   }
536 
537   /// Return the actual namespace token, if this token starts a namespace
538   /// block.
539   const FormatToken *getNamespaceToken() const {
540     const FormatToken *NamespaceTok = this;
541     if (is(tok::comment))
542       NamespaceTok = NamespaceTok->getNextNonComment();
543     // Detect "(inline|export)? namespace" in the beginning of a line.
544     if (NamespaceTok && NamespaceTok->isOneOf(tok::kw_inline, tok::kw_export))
545       NamespaceTok = NamespaceTok->getNextNonComment();
546     return NamespaceTok &&
547                    NamespaceTok->isOneOf(tok::kw_namespace, TT_NamespaceMacro)
548                ? NamespaceTok
549                : nullptr;
550   }
551 
552 private:
553   // Disallow copying.
554   FormatToken(const FormatToken &) = delete;
555   void operator=(const FormatToken &) = delete;
556 
557   template <typename A, typename... Ts>
558   bool startsSequenceInternal(A K1, Ts... Tokens) const {
559     if (is(tok::comment) && Next)
560       return Next->startsSequenceInternal(K1, Tokens...);
561     return is(K1) && Next && Next->startsSequenceInternal(Tokens...);
562   }
563 
564   template <typename A> bool startsSequenceInternal(A K1) const {
565     if (is(tok::comment) && Next)
566       return Next->startsSequenceInternal(K1);
567     return is(K1);
568   }
569 
570   template <typename A, typename... Ts> bool endsSequenceInternal(A K1) const {
571     if (is(tok::comment) && Previous)
572       return Previous->endsSequenceInternal(K1);
573     return is(K1);
574   }
575 
576   template <typename A, typename... Ts>
577   bool endsSequenceInternal(A K1, Ts... Tokens) const {
578     if (is(tok::comment) && Previous)
579       return Previous->endsSequenceInternal(K1, Tokens...);
580     return is(K1) && Previous && Previous->endsSequenceInternal(Tokens...);
581   }
582 };
583 
584 class ContinuationIndenter;
585 struct LineState;
586 
587 class TokenRole {
588 public:
589   TokenRole(const FormatStyle &Style) : Style(Style) {}
590   virtual ~TokenRole();
591 
592   /// After the \c TokenAnnotator has finished annotating all the tokens,
593   /// this function precomputes required information for formatting.
594   virtual void precomputeFormattingInfos(const FormatToken *Token);
595 
596   /// Apply the special formatting that the given role demands.
597   ///
598   /// Assumes that the token having this role is already formatted.
599   ///
600   /// Continues formatting from \p State leaving indentation to \p Indenter and
601   /// returns the total penalty that this formatting incurs.
602   virtual unsigned formatFromToken(LineState &State,
603                                    ContinuationIndenter *Indenter,
604                                    bool DryRun) {
605     return 0;
606   }
607 
608   /// Same as \c formatFromToken, but assumes that the first token has
609   /// already been set thereby deciding on the first line break.
610   virtual unsigned formatAfterToken(LineState &State,
611                                     ContinuationIndenter *Indenter,
612                                     bool DryRun) {
613     return 0;
614   }
615 
616   /// Notifies the \c Role that a comma was found.
617   virtual void CommaFound(const FormatToken *Token) {}
618 
619   virtual const FormatToken *lastComma() { return nullptr; }
620 
621 protected:
622   const FormatStyle &Style;
623 };
624 
625 class CommaSeparatedList : public TokenRole {
626 public:
627   CommaSeparatedList(const FormatStyle &Style)
628       : TokenRole(Style), HasNestedBracedList(false) {}
629 
630   void precomputeFormattingInfos(const FormatToken *Token) override;
631 
632   unsigned formatAfterToken(LineState &State, ContinuationIndenter *Indenter,
633                             bool DryRun) override;
634 
635   unsigned formatFromToken(LineState &State, ContinuationIndenter *Indenter,
636                            bool DryRun) override;
637 
638   /// Adds \p Token as the next comma to the \c CommaSeparated list.
639   void CommaFound(const FormatToken *Token) override {
640     Commas.push_back(Token);
641   }
642 
643   const FormatToken *lastComma() override {
644     if (Commas.empty())
645       return nullptr;
646     return Commas.back();
647   }
648 
649 private:
650   /// A struct that holds information on how to format a given list with
651   /// a specific number of columns.
652   struct ColumnFormat {
653     /// The number of columns to use.
654     unsigned Columns;
655 
656     /// The total width in characters.
657     unsigned TotalWidth;
658 
659     /// The number of lines required for this format.
660     unsigned LineCount;
661 
662     /// The size of each column in characters.
663     SmallVector<unsigned, 8> ColumnSizes;
664   };
665 
666   /// Calculate which \c ColumnFormat fits best into
667   /// \p RemainingCharacters.
668   const ColumnFormat *getColumnFormat(unsigned RemainingCharacters) const;
669 
670   /// The ordered \c FormatTokens making up the commas of this list.
671   SmallVector<const FormatToken *, 8> Commas;
672 
673   /// The length of each of the list's items in characters including the
674   /// trailing comma.
675   SmallVector<unsigned, 8> ItemLengths;
676 
677   /// Precomputed formats that can be used for this list.
678   SmallVector<ColumnFormat, 4> Formats;
679 
680   bool HasNestedBracedList;
681 };
682 
683 /// Encapsulates keywords that are context sensitive or for languages not
684 /// properly supported by Clang's lexer.
685 struct AdditionalKeywords {
686   AdditionalKeywords(IdentifierTable &IdentTable) {
687     kw_final = &IdentTable.get("final");
688     kw_override = &IdentTable.get("override");
689     kw_in = &IdentTable.get("in");
690     kw_of = &IdentTable.get("of");
691     kw_CF_CLOSED_ENUM = &IdentTable.get("CF_CLOSED_ENUM");
692     kw_CF_ENUM = &IdentTable.get("CF_ENUM");
693     kw_CF_OPTIONS = &IdentTable.get("CF_OPTIONS");
694     kw_NS_CLOSED_ENUM = &IdentTable.get("NS_CLOSED_ENUM");
695     kw_NS_ENUM = &IdentTable.get("NS_ENUM");
696     kw_NS_OPTIONS = &IdentTable.get("NS_OPTIONS");
697 
698     kw_as = &IdentTable.get("as");
699     kw_async = &IdentTable.get("async");
700     kw_await = &IdentTable.get("await");
701     kw_declare = &IdentTable.get("declare");
702     kw_finally = &IdentTable.get("finally");
703     kw_from = &IdentTable.get("from");
704     kw_function = &IdentTable.get("function");
705     kw_get = &IdentTable.get("get");
706     kw_import = &IdentTable.get("import");
707     kw_infer = &IdentTable.get("infer");
708     kw_is = &IdentTable.get("is");
709     kw_let = &IdentTable.get("let");
710     kw_module = &IdentTable.get("module");
711     kw_readonly = &IdentTable.get("readonly");
712     kw_set = &IdentTable.get("set");
713     kw_type = &IdentTable.get("type");
714     kw_typeof = &IdentTable.get("typeof");
715     kw_var = &IdentTable.get("var");
716     kw_yield = &IdentTable.get("yield");
717 
718     kw_abstract = &IdentTable.get("abstract");
719     kw_assert = &IdentTable.get("assert");
720     kw_extends = &IdentTable.get("extends");
721     kw_implements = &IdentTable.get("implements");
722     kw_instanceof = &IdentTable.get("instanceof");
723     kw_interface = &IdentTable.get("interface");
724     kw_native = &IdentTable.get("native");
725     kw_package = &IdentTable.get("package");
726     kw_synchronized = &IdentTable.get("synchronized");
727     kw_throws = &IdentTable.get("throws");
728     kw___except = &IdentTable.get("__except");
729     kw___has_include = &IdentTable.get("__has_include");
730     kw___has_include_next = &IdentTable.get("__has_include_next");
731 
732     kw_mark = &IdentTable.get("mark");
733 
734     kw_extend = &IdentTable.get("extend");
735     kw_option = &IdentTable.get("option");
736     kw_optional = &IdentTable.get("optional");
737     kw_repeated = &IdentTable.get("repeated");
738     kw_required = &IdentTable.get("required");
739     kw_returns = &IdentTable.get("returns");
740 
741     kw_signals = &IdentTable.get("signals");
742     kw_qsignals = &IdentTable.get("Q_SIGNALS");
743     kw_slots = &IdentTable.get("slots");
744     kw_qslots = &IdentTable.get("Q_SLOTS");
745 
746     // C# keywords
747     kw_dollar = &IdentTable.get("dollar");
748     kw_base = &IdentTable.get("base");
749     kw_byte = &IdentTable.get("byte");
750     kw_checked = &IdentTable.get("checked");
751     kw_decimal = &IdentTable.get("decimal");
752     kw_delegate = &IdentTable.get("delegate");
753     kw_event = &IdentTable.get("event");
754     kw_fixed = &IdentTable.get("fixed");
755     kw_foreach = &IdentTable.get("foreach");
756     kw_implicit = &IdentTable.get("implicit");
757     kw_internal = &IdentTable.get("internal");
758     kw_lock = &IdentTable.get("lock");
759     kw_null = &IdentTable.get("null");
760     kw_object = &IdentTable.get("object");
761     kw_out = &IdentTable.get("out");
762     kw_params = &IdentTable.get("params");
763     kw_ref = &IdentTable.get("ref");
764     kw_string = &IdentTable.get("string");
765     kw_stackalloc = &IdentTable.get("stackalloc");
766     kw_sbyte = &IdentTable.get("sbyte");
767     kw_sealed = &IdentTable.get("sealed");
768     kw_uint = &IdentTable.get("uint");
769     kw_ulong = &IdentTable.get("ulong");
770     kw_unchecked = &IdentTable.get("unchecked");
771     kw_unsafe = &IdentTable.get("unsafe");
772     kw_ushort = &IdentTable.get("ushort");
773 
774     // Keep this at the end of the constructor to make sure everything here
775     // is
776     // already initialized.
777     JsExtraKeywords = std::unordered_set<IdentifierInfo *>(
778         {kw_as, kw_async, kw_await, kw_declare, kw_finally, kw_from,
779          kw_function, kw_get, kw_import, kw_is, kw_let, kw_module, kw_readonly,
780          kw_set, kw_type, kw_typeof, kw_var, kw_yield,
781          // Keywords from the Java section.
782          kw_abstract, kw_extends, kw_implements, kw_instanceof, kw_interface});
783 
784     CSharpExtraKeywords = std::unordered_set<IdentifierInfo *>(
785         {kw_base, kw_byte, kw_checked, kw_decimal, kw_delegate, kw_event,
786          kw_fixed, kw_foreach, kw_implicit, kw_in, kw_interface, kw_internal,
787          kw_is, kw_lock, kw_null, kw_object, kw_out, kw_override, kw_params,
788          kw_readonly, kw_ref, kw_string, kw_stackalloc, kw_sbyte, kw_sealed,
789          kw_uint, kw_ulong, kw_unchecked, kw_unsafe, kw_ushort,
790          // Keywords from the JavaScript section.
791          kw_as, kw_async, kw_await, kw_declare, kw_finally, kw_from,
792          kw_function, kw_get, kw_import, kw_is, kw_let, kw_module, kw_readonly,
793          kw_set, kw_type, kw_typeof, kw_var, kw_yield,
794          // Keywords from the Java section.
795          kw_abstract, kw_extends, kw_implements, kw_instanceof, kw_interface});
796   }
797 
798   // Context sensitive keywords.
799   IdentifierInfo *kw_final;
800   IdentifierInfo *kw_override;
801   IdentifierInfo *kw_in;
802   IdentifierInfo *kw_of;
803   IdentifierInfo *kw_CF_CLOSED_ENUM;
804   IdentifierInfo *kw_CF_ENUM;
805   IdentifierInfo *kw_CF_OPTIONS;
806   IdentifierInfo *kw_NS_CLOSED_ENUM;
807   IdentifierInfo *kw_NS_ENUM;
808   IdentifierInfo *kw_NS_OPTIONS;
809   IdentifierInfo *kw___except;
810   IdentifierInfo *kw___has_include;
811   IdentifierInfo *kw___has_include_next;
812 
813   // JavaScript keywords.
814   IdentifierInfo *kw_as;
815   IdentifierInfo *kw_async;
816   IdentifierInfo *kw_await;
817   IdentifierInfo *kw_declare;
818   IdentifierInfo *kw_finally;
819   IdentifierInfo *kw_from;
820   IdentifierInfo *kw_function;
821   IdentifierInfo *kw_get;
822   IdentifierInfo *kw_import;
823   IdentifierInfo *kw_infer;
824   IdentifierInfo *kw_is;
825   IdentifierInfo *kw_let;
826   IdentifierInfo *kw_module;
827   IdentifierInfo *kw_readonly;
828   IdentifierInfo *kw_set;
829   IdentifierInfo *kw_type;
830   IdentifierInfo *kw_typeof;
831   IdentifierInfo *kw_var;
832   IdentifierInfo *kw_yield;
833 
834   // Java keywords.
835   IdentifierInfo *kw_abstract;
836   IdentifierInfo *kw_assert;
837   IdentifierInfo *kw_extends;
838   IdentifierInfo *kw_implements;
839   IdentifierInfo *kw_instanceof;
840   IdentifierInfo *kw_interface;
841   IdentifierInfo *kw_native;
842   IdentifierInfo *kw_package;
843   IdentifierInfo *kw_synchronized;
844   IdentifierInfo *kw_throws;
845 
846   // Pragma keywords.
847   IdentifierInfo *kw_mark;
848 
849   // Proto keywords.
850   IdentifierInfo *kw_extend;
851   IdentifierInfo *kw_option;
852   IdentifierInfo *kw_optional;
853   IdentifierInfo *kw_repeated;
854   IdentifierInfo *kw_required;
855   IdentifierInfo *kw_returns;
856 
857   // QT keywords.
858   IdentifierInfo *kw_signals;
859   IdentifierInfo *kw_qsignals;
860   IdentifierInfo *kw_slots;
861   IdentifierInfo *kw_qslots;
862 
863   // C# keywords
864   IdentifierInfo *kw_dollar;
865   IdentifierInfo *kw_base;
866   IdentifierInfo *kw_byte;
867   IdentifierInfo *kw_checked;
868   IdentifierInfo *kw_decimal;
869   IdentifierInfo *kw_delegate;
870   IdentifierInfo *kw_event;
871   IdentifierInfo *kw_fixed;
872   IdentifierInfo *kw_foreach;
873   IdentifierInfo *kw_implicit;
874   IdentifierInfo *kw_internal;
875 
876   IdentifierInfo *kw_lock;
877   IdentifierInfo *kw_null;
878   IdentifierInfo *kw_object;
879   IdentifierInfo *kw_out;
880 
881   IdentifierInfo *kw_params;
882 
883   IdentifierInfo *kw_ref;
884   IdentifierInfo *kw_string;
885   IdentifierInfo *kw_stackalloc;
886   IdentifierInfo *kw_sbyte;
887   IdentifierInfo *kw_sealed;
888   IdentifierInfo *kw_uint;
889   IdentifierInfo *kw_ulong;
890   IdentifierInfo *kw_unchecked;
891   IdentifierInfo *kw_unsafe;
892   IdentifierInfo *kw_ushort;
893 
894   /// Returns \c true if \p Tok is a true JavaScript identifier, returns
895   /// \c false if it is a keyword or a pseudo keyword.
896   bool IsJavaScriptIdentifier(const FormatToken &Tok) const {
897     return Tok.is(tok::identifier) &&
898            JsExtraKeywords.find(Tok.Tok.getIdentifierInfo()) ==
899                JsExtraKeywords.end();
900   }
901 
902   /// Returns \c true if \p Tok is a C# keyword, returns
903   /// \c false if it is a anything else.
904   bool isCSharpKeyword(const FormatToken &Tok) const {
905     switch (Tok.Tok.getKind()) {
906     case tok::kw_bool:
907     case tok::kw_break:
908     case tok::kw_case:
909     case tok::kw_catch:
910     case tok::kw_char:
911     case tok::kw_class:
912     case tok::kw_const:
913     case tok::kw_continue:
914     case tok::kw_default:
915     case tok::kw_do:
916     case tok::kw_double:
917     case tok::kw_else:
918     case tok::kw_enum:
919     case tok::kw_explicit:
920     case tok::kw_extern:
921     case tok::kw_false:
922     case tok::kw_float:
923     case tok::kw_for:
924     case tok::kw_goto:
925     case tok::kw_if:
926     case tok::kw_int:
927     case tok::kw_long:
928     case tok::kw_namespace:
929     case tok::kw_new:
930     case tok::kw_operator:
931     case tok::kw_private:
932     case tok::kw_protected:
933     case tok::kw_public:
934     case tok::kw_return:
935     case tok::kw_short:
936     case tok::kw_sizeof:
937     case tok::kw_static:
938     case tok::kw_struct:
939     case tok::kw_switch:
940     case tok::kw_this:
941     case tok::kw_throw:
942     case tok::kw_true:
943     case tok::kw_try:
944     case tok::kw_typeof:
945     case tok::kw_using:
946     case tok::kw_virtual:
947     case tok::kw_void:
948     case tok::kw_volatile:
949     case tok::kw_while:
950       return true;
951     default:
952       return Tok.is(tok::identifier) &&
953              CSharpExtraKeywords.find(Tok.Tok.getIdentifierInfo()) ==
954                  CSharpExtraKeywords.end();
955     }
956   }
957 
958 private:
959   /// The JavaScript keywords beyond the C++ keyword set.
960   std::unordered_set<IdentifierInfo *> JsExtraKeywords;
961 
962   /// The C# keywords beyond the C++ keyword set
963   std::unordered_set<IdentifierInfo *> CSharpExtraKeywords;
964 };
965 
966 } // namespace format
967 } // namespace clang
968 
969 #endif
970